Enclosure for an electrical terminal block including barrier means for a cable entry opening

ABSTRACT

An enclosure for an electrical terminal block includes a housing having a back wall and projecting side walls extending thereabout to form a bounded chamber. One side wall includes an opening formed therethrough for permitting passage of an electrical cable into the bounded chamber. A barrier member is supported by the side wall adjacent the opening. The barrier member includes a barrier wall at least partially surrounding the opening about a periphery thereof. The barrier member includes a pair of elongate oppositely directed deflectable fingers projecting inwardly from the barrier wall. Distal ends of the oppositely directed fingers overlap to close-off the opening.

FIELD OF INVENTION:

The present invention relates to an enclosure for an electrical terminalblock, the enclosure having an opening therein which permits entry of anelectrical cable. More particularly, the present invention relates to abarrier member which closes the cable entry opening.

BACKGROUND OF THE INVENTION

Electrical enclosures have long been used in both power transmission andtelecommunications transmission to house devices which terminateelectrical wires or cables. These terminal devices referred to as"terminal blocks", are supported inside the enclosure. Openings areprovided through the enclosure so that electrical cables may be passedtherethrough for electrical termination to the terminal blocks. Whenenclosures such as these are used outdoors, they are exposed to theelements. Water, which may enter the enclosure through the cable entryopenings, could adversely affect the connections of the cables to theterminal block.

The art has seen a variety of barrier type devices which permit passageof the cable through the opening, yet restrict moisture passagetherethrough. U.S. Pat. No. 3,523,156 shows an improved moisture barrierfor an electrical pedestal. The device includes a rubber sealing memberhaving openings therethrough in line with the cable entry openings. Theopening in the sealing member surrounds the electrical cable in sealingengagement, restricting the tendency of water to track along the cableand into the enclosure. However, in order to prevent water from enteringthe cable entry opening when a cable is not inserted therethrough, aseparate plug must be inserted therein. The limitations of such aseparate plug are readily apparent.

Other enclosures include rubber sealing members including a thinmembrane which spans the cable entry opening, thus effectively closingthe opening when no cable is inserted therethrough. To provide cableaccess through a particular opening, the cable is inserted through themembrane to puncture the membrane, thus providing access to the interiorof the enclosure. However, with these membrane-type sealing devices,once the cable is removed, the membrane is violated and water passagetherethrough is not restricted.

It is desirable to provide an enclosure for an electrical terminal blockhaving cable entry openings, which provides a moisture barrier at thecable entry opening. The moisture barrier should effectively restrictwater from passing therethrough prior to cable insertion, while thecable is inserted and after the cable has been removed.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an enclosure for anelectrical terminal block which permits entry of electrical cablesthrough openings therein and which seals the openings, minimizing waterpassage therethrough.

It is a further object of the present invention to provide a barriermember for covering an opening in electrical terminal block enclosure.The barrier member should restrict water passage through the opening,yet permitting insertion and removal of an electrical cabletherethrough.

In the efficient attainment of these and other objects, the presentinvention provides an enclosure for an electrical terminal blockincluding a housing which supports the electrical terminal blocktherein. The housing includes an opening through a wall thereof topermit passage of an electrical cable therethrough. Barrier meanssupported by the wall adjacent the opening includes a barrier wall atleast partially surrounding the opening about a periphery thereof. Apair of elongate oppositely directly deflectable fingers projectinwardly from the barrier wall into the opening. Distal ends of theoppositly directed fingers overlap to close-off the opening.

As particularly shown by way of a preferred embodiment herein, thepresent invention provides an enclosure including a terminal box definedby a back wall, side walls and a cover. One of the side walls includes aplurality of longitudinal cable entry slots, which provide passage forplural electrical cables. Each slot includes a longitudinal extent and atransverse extent. Barrier means covers the cable entry slots andincludes barrier fingers which extend transversely along eachlongitudinal side of the slot and inwardly toward each other. Distalextents of the fingers extend beyond the center of the slot to overlapeach other to close-off the slot.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective showing of an enclosure for an electricalterminal block in accordance with the present invention.

FIGS. 2 and 3 show in bottom and front plan views respectively, one wallof the enclosure of FIG. 1.

FIG. 4 is a partial sectional showing of the wall of FIG. 2 including aninsulative barrier member molded therearound.

FIG. 5 is a partial perspective showing of the wall and the barriermember of FIG. 4 with an electrical cable inserted therein.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Electrical enclosure 10 of the present invention is typically a box-typemember formed of sheet metal or similar material. Enclosure 10 is formedto have a flat planar back wall 12 and a substantially continuous sidewall 14 projecting therefrom. Side wall 14 may be integrally formed or,as shown in the embodiment of FIG. 1, may include discrete upper andlower wall segments 16 and 18, as well as side-by-side wall segments 20and 22. Back wall 12 and side wall 14 define a bounded chamber 24interiorly thereof, which is designed to support therein an electricalterminal block (not shown) used for electrical interconnections.Enclosure 10 further includes a plate-like cover 26 hingedly attached toside wall segment 22 with hinge 28. Cover 26 is opened to access theterminal block housed in chamber 24 and may be closed to provide acompletely bounded closure. Enclosure 10 permits entry of electricalcables 30 thereinto for electrical termination with the terminal blocksupported in chamber 24.

Referring to FIGS. 2 and 3, cable access is provided by a plurality ofslots 32 located through lower wall segment 18. Each of slots 32 is anelongate member having a generally rectangular shape. Each slot isdefined by a longitudinal dimension as well as a transverse dimension.As particularly shown in FIG. 3, lower wall segment 18 includesdepending stiffener members 34, which provide rigidity to the lower wallsegment 18 between slots 32. Slots 32 are arranged in spacedside-by-side orientation along lower wall segment 18. This permitsinsertion of the plural electrical cables into enclosure 10.

Referring again to FIG. 1, typical cable insertion occurs by insertingthe end of 31 of electrical cable 30 in a direction along thelongitudinal axis of enclosure 10 (arrow A). One or more electricalcables 30 may be inserted through each slot 32. In typical use,enclosure 10 is installed outdoors either on a utility pole or as partof an above-ground pedestal. Therefore, provisions must be made torestrict water from tracking through slots 32 provided for insertion ofelectrical cable 30.

The present invention employs a barrier member 40 which is molded aboutlower wall segment 18. Referring to FIGS. 4 and 5, barrier member 40 isformed of a suitable elastomer or rubber. Barrier member 40 is molded indirect adherence to lower wall segment 18 to cover slots 32, as well asdepending stiffener members 34. Barrier member 40 is formed to have anupper surface 42 extending over and across all of slots 32. Barriermember 40 further includes a location 44 of reduced thickness adjacentto and over each of slots 32. Each of locations 44 is formed to have aplurality of inwardly directed fingers 46. As shown in FIG. 4, fingers46 extend from opposed peripheral longitudinal edges 32a of slots 32inwardly toward each other. At least one finger 46 extends from eachlongitudinal edge 32a. In the present invention three inwardly directedfingers 46 are shown adjacent each slot 32. However, this number mayvary. Each finger 46 extends more than halfway across the transverseextent of slot 32. Thus opposed adjacent fingers 46 overlap at distalextents 46a thereof. The center line 1 of each slot 32 is shown in FIG.4. Distal extents 46a of fingers 46 extend beyond this center line 1.The overlapping of distal extents 46a of fingers 46 serves to close-offslots 32, preventing the inward migration of water therethrough.Inwardly directly fingers 46 essentially define a zigzag path whichimpedes the flow of water through slots 32.

A further feature of the present invention is shown in FIG. 4. Uppersurface 42 of barrier member 40 includes a thin membrane 48 directlyover each slot 32 Membrane 48 covers slot 32, completely closing off theslot as long as no electrical cable 30 is inserted therethrough. Thus,any one of slots 32 which is unused will be completely sealed againstwater propagation therethrough. Membrane 48 is relatively thin andeasily puncturable by the insertion of cable 30 therethrough, to permitaccess to the interior of enclosure 10 (FIG. 1).

Referring to FIGS. 1 and 5, it can be seen that electrical cable 30 maybe inserted through slot 32 from below along the direction of arrow A.Upon insertion, each of distal ends 46a of fingers 46 contacts cable 30.Membrane 48 is ruptured upon insertion of cable 30 therethrough. Thedistal ends 46a of fingers 46, as well as the newly formed fingerportions 49 adjacent the ruptured membrane 48, will deflect and bearagainst cable 30 in sealing relation to prevent water from trackingalong the cable 30 and into enclosure 10. If during subsequent use cable30 is removed, fingers 46 will deflect back to their original positionshown in FIG. 4, where the distal ends 46a again extend beyond centerline 1 to overlap one another, closing off slot 32 and restricting waterfrom entering enclosure 10.

Various changes to the foregoing described and shown structures wouldnow be evident to those skilled in the art. Accordingly, theparticularly disclosed scope of the invention is set forth in thefollowing claims.

I claim:
 1. An enclosure for an electrical terminal block and electricalcables terminated to said terminal block, said enclosure comprising:ahousing having a back wall and a side wall projecting therefrom andextending thereabout to form a bounded chamber interiorly thereof, saidterminal block being supported within said chamber; said side wallincluding an opening formed therethrough for permitting passage of anelectrical cable into said bounded chamber; barrier means supported bysaid side wall adjacent said opening, said barrier means including abarrier wall at least partially surrounding said opening about aperiphery thereof and a pair of elongate oppositely directed deflectablefingers projecting inwardly from said barrier wall into said opening,distal ends of said oppositely directed fingers overlapping to close-offsaid opening; and a cover movably supported by said side wall forenclosing said terminal block.
 2. An enclosure in accordance with claim1 wherein said deflectable fingers of said pair are vertically spaced.3. An enclosure in accordance with claim 1 wherein said barrier meansincludes an additional deflectable finger extending from said barrierwall vertically spaced from and substantially parallel to one finger ofsaid pair, said additional deflectable finger having a distal endoverlapping said distal end of the other finger of said pair.
 4. Anenclosure in accordance with claim 1 wherein said barrier means includesa puncturable membrane spanning said opening to additionally close-offsaid opening.
 5. An enclosure in accordance with claim 4 wherein saidmembrane is puncturable upon said passage of said electrical cabletherethrough.
 6. An enclosure in accordance with claim 1 wherein saidopening formed through said side wall is an elongate slot having atransverse extent defined by spaced apart longitudinal slot side edges.7. An enclosure in accordance with claim 6 wherein said barrier wallextends along said slot side edges, said pair of deflectable fingersextending along the longitudinal extent of said slot to close-off saidslot transverse extent.
 8. An enclosure in accordance with claim 7wherein said barrier means includes an additional deflectable fingerextending from said barrier wall spaced from and substantially parallelto one finger of said pair, said additional finger having a distal endoverlapping said distal end of the other finger of said pair.
 9. Anenclosure in accordance with claim 7 wherein said barrier means includesa puncturable membrane spanning said traverse extent of said slot, saidmembrane being puncturable upon insertion of said cable in said slot.10. An enclosure in accordance with claim 6 wherein said slot permitsaccommodation of plural electrical cables.
 11. An electrical enclosurecomprising:a box including a back wall, side walls and an cover defininga chamber therein for supporting an electrical terminal device; aplurality of longitudinal cable entry slots spaced along one of saidside walls for providing passage for plural electrical cables, each ofsaid slots having a longitudinal extent extending along a longitudinalcenter line and a transverse extent; and barrier means covering saidcable entry slots, said barrier means including a barrier fingerextending transversely from each longitudinal side of each said slot,each of said fingers extending beyond the longitudinal center line ofeach said slot.
 12. An electrical enclosure of claim 11 wherein saidbarrier means includes a puncturable membrane across each said slottransverse extent, each said membrane being puncturable upon saidpassage of one of said plural electrical cables therethrough.
 13. Anelectrical enclosure of claim 12 wherein said barrier fingers areresiliently deflectable for permitting passage of said electrical cablestherethrough.
 14. An electrical enclosure of claim 13 wherein saidbarrier fingers include distal extents for sealing engagement with saidcables upon said passage therethrough.
 15. A barrier for covering anopening in an electrical box, said opening being defined by spacedperipheral edges on opposed sides of a center point, said barriercomprising:a first barrier finger extending from one peripheral edge ofsaid opening, an end portion of said first barrier finger extendingbeyond said opening center point; and a second barrier finger extendingfrom another peripheral edge of said opening, an end portion of saidsecond barrier finger extending beyond said center point, said endportions of said first and second barrier fingers overlapping toclose-off said opening.
 16. A barrier of claim 15 further including athird barrier finger extending from one peripheral edge of said opening,an end portion of said third barrier finger extending beyond said centerpoint.
 17. A barrier of claim 16 further including a puncturablemembrane extending across side opening.